Understanding how sensors really work and use different sensors to accomplish the same goal.

Lesson Objectives:

To understand how the ultrasonic sensor works. Use two sensors to accomplish same goal.

Materials Needed:

Already built NXT car, bouncy ball to demonstrate ultrasonic sensor, flashlight maybe to demonstrate how the light sensor senses both reflected and ambient light and the difference between the two.

Preparation and Set Up:

Already built car and a thorough understanding of how the sensors truly work.

Necessary Background

Understand how the sensors are able to accurately sense whatever it is they sense.

Procedure

In order to understand how untrasonic sensors work, children can throw a bouncy ball against a wall from different distances and see how it takes longer to come back to them when they are farther and less time when they are closer. In order to understand how the light sensor works, they should pull up the real time reading of the light sensor on the brick and hold it up to different lightings and see how the reading changes and test how it is different when sensing reflection as opposed to ambient light and use these readings to set the threshold to put in the program. A flashlight can also be held up to a piece of paper at different distances and see how the intensity changes. The challenge will then be to have a car go back and forth between two walls using the ultrasonic sensor on one side and the light sensor on the other side.

Extensions:

Use a different sensor as well to accomplish the same goal if a group is far ahead.